Boiler tube gauge



Aug. 7, 1951 A. L. DALE BOILER TUBE GAUGE Filed May 27. 1947 Invntor Allen L'. Dale BJ' z L.

Patented Aug. 7, 1951 ;i

BoILERrTUB- o'fnUGE i i |Allan VL. Dale, san Lake ity, Utah i Application May-27, 1947;;seri1fN0. fzsog'rfaci The :present invention relates to new and useful improvements iniboiler tube .gages to check defectszor weak spots in the tubes` The invention is designed particularly for use with fire tube boilersvof a catalytic cracking unit in refineries wherein the tubes are of considerablefl'en'gth and generallyrinaccessible forinspection. The high Velocity, hot abrasive Catalyst has a tendency to create a cyclone action in the tube which reduces the thickness ofthe walls of 'the tube in pockets and the invention has for an important object toA locate .such 'defects inizthe tube before a break therein occurs.

A further object is tofrprov'ide atesting device or gage which may be drawnV through a tube and embodying electric signalling means to. indicate a spot in the tube wherea Idefect therein has occurred.

Another object is to provide a tube testing device having self-contained electric signalling means therein.

Another object is to provide a device of this character of simple and practical construction, which is efiicient and reliable in operation, relatively inexpensive to manufacture and otherwise well adapted for the purpose for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a longitudinal sectional view;

Figure 2 is a side elevational view;

Figure 3 is an enlarged transverse sectional view taken on a line 3--3 of Figure 1;

Figure 4 is a fragmentary longitudinal sectional view of the connector of the upper and lower ends of the barrel;

Figure 5 is a fragmentary end elevational view thereof;

Figure 6 is an enlarged transverse sectional view taken on a line 6-6 of Figure 1; and

Figure 7 is an enlarged fragmentary sectional view of one of the pivoted gage arms showing the anti-frction ball carried thereby.

Referring now to the drawing in' detail, wherein, for the purpose of illustration, I have disclosed a preferred embodiment of my invention, the numeral 5 designates a barrel composed of upper and lower Sections 6 and 1, respectively, connected to each other in longitudinally spaced relation by a cylindrical connector 8 having its ends inserted in the adjacent ends of the Sections of the barrel and secured thereto by screws 9.

The. connector 8- is formedwitna: pluralitzof longitudinally 'extending" slots In providedwith transverse pins i I and on which arms |2zil'a`re friction-.co'ntact with thelinteriofr of 'a tube'when the -barreliis-` drawn therethr'ough. A' wire spring [5 is' positioned in? the lower section; 'll of'th'e barrel against the lower end ofv therarmzto pr`o= je'ct the head. |3` outwardly 'against' the wall 'of thetube. i

A flan'ge'd ibushing l'offinsulation materialfiis inserted in the upper end of the connector 8 'in which a lower conductor rod l'l is slidably adjusted, the lower end of the rod having a conical head 18 in position for contact by the lower ends of the arms 12. The rod l'l and head |8 are adjusted longitudinally in the barrel by a set screw [9 threaded longitudinally in a lower plug 20 secured in the lower end of the barrel section 'l by an insulation sleeve 2|. A lock nut 22 secures the screw |9 in adjusted position.

A conventional fiashlight battery 23 is supported in the upper section 6 of the barrel by an insulation sleeve 24 and the base of the battery is engaged by an upper conductor rod 25 under spring tension by a |coil spring 26 surrounding the adjacent ends of rods I'l and 25 between a flange 21 on the lower rod and a head 28-on the upper rod and enclosed in a guide sleeve 29 to hold the rods rigidly alined longitudinally.

The upper end of the battery contacts the base of a lamp 30 mounted in a socket 3| in the upper barrel section and the lamp is enclosed in the lower end of a Lucite cap 32 secured in the upper end of the barrel. A ring or bail 33 is attached to the cap 32 and to which a steel measuring tape (not shown) may be attached for raising or lowering the barrel in a boiler tube to be tested.

In the operation of the device, the heads |3 of arms l2 are projected radially outwardly of the barrel by the Springs so that the anti-friction balls ride against the inside of a boiler tube. The conical head is adjusted to normally maintain the inner lower ends of the arms |2 spaced from the head Whereby the circuit for the lamp remains open when the barrel passes through a tube of uniform predetermined internal diameter. When the balls encounter internal depressions or pockets in the tube caused by wear in 1...; 3 the walls thereof, the outward radial movement of the heads of the arms |2, when entering such depressions, will permit Springs to move the lower ends of the arms into contact with the conical head and thus close the circuit to energize the lamp to indicate a defect in the tube.

The use of a measuring tape in raising or lowering the barrel in the tube will indicate the position of the defect.

In view of the foregoing description taken in conjunction with the accompanying drawings, it is believed that a clear understanding of the device will be quite apparent to those sklled in this` art. A more detailed description is accordingly deemed unnecessary. i

It is to be understood, however, that even though there is herein shown and described a aueaaie Z projecting radially outwardly of the barrel to travel along the bore of a tube, the inner ends of said arms having circuit closing engagement with said head upon a predetermined outward movement of said arms, and adjusting means for ;said conductor to regulate the circuit closing preferred embodiment of the invention, the same 4 is susceptible to certain changes fully comprehended by thespirit of the 'lnvention as herein described and Within the scope of the appended claims. i

Having described the invention, what is claimed asnewis:

1. A boiler tube testing device comprising a barrel, a plurality of spring-biased gage arms pivoted in the barrel and having one end projecting radially outwardly of the barrel for travelling along the bore of a tube, a self-contained electric signal in the barrel, andV switch means forsaid signal of which said arms are a part for closing a circuit with said signal upon a predetermined outward movement of said arms, Said switch means including a cone-shaped contact slidably mounted in the barrel, and adjusting means carried at an adjacent end of the movement of the arms with the head.

ALLAN L. DALE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Date 

